Pole finder



F. B. ACOSTA POLE FINDER Dec. 19, 1933.

:ICE-Elil-Em Filed May 9, 1930 lPatented Dec. 19, 1933 UNITED STATES PATENT OFFICE 1,940,521 POLE FINDER Felipe B. Acosta, New York, N. Y. Application May 9, 1930. Serial No. 451,188

(Cl. F75-183) My present invention has and novel electric polarity object is the provision of a po 1 Claim.

cket size instrument for this purpose which Will readily and positively indicate the direction of electric currents (D. C.) which will locate the positive and negative poles of any direct current source, which will determine Whether the line circuit tested is or direct current and Which will locate alternating short circuits and broken connections in radio sets,

etc.

To the attainment of the foregoing the invention consists in the improvement hereinafter described and denitely claimed.

In the drawing:V

nal sectional view therethrou Figure 3 is a transverse proximately on the line 3-3 sectional View apof Figure 2.

As disclosed by the drawing the improvement comprises a cylindrical casing which is small in size and has extending therefrom a sleeve 2 whose ends are closed.

In the casing l there is fixed a horseshoe magnet 3 and pivoted centrally in the casing, in a line with the ends of the magnet 3, there is a needle pointer 4 Whose arrow 4 head is for distinction indicated by the numeral 5. The pivot of the needle 4 is indicated by the numeral 4. The ends of th e horseshoe magnet are arranged in horizontal alignment in the casing l and at opposite sides of the pivot 4' of the magnetized needle 4, thereby normally sustaining the needle in an immovable and stable position.

In thesleeve 2 there is arranged an electromagnet 6 having the outer connected to a binding upper closed end of the tering said sleeve, passing the core the binding post '7 there is end of its Winding post l secured onthe sleeve 2 and partly enof the magnet also through the second end of the sleeve and being partly received in the casing 1.

To connected a cord 8 Whose outer end is provided with a metal tip 9. The Winding at the magnet 6 is provided with or to a conductor Wire 6'. through the casing and is s inner end of the electrohas attached there- The Wire 6' is directed ecured to a binding Vsecured thereon a second cord l1 Whose end is provided With a metal tip 12. The operation of the improvement may be briefly described as i follows: When the current enters through the tip 9 and passes through the tip 12 the end of the electromagnet attached to the casing 1Y becomes the north pole and attracts the south pole and repels the north pole of the magnetic needle 4. The head 0r pointer 5 of the needle points toward the direction of the current. Should the current be reversed so that Y it enters through the tip l2 to the tip 9, the inner end of the electromagnet becomes the south pole and attracts the north pole and repels the south pole of the magnetic needle. Againthe needle points toward the direction of the current. An alternating current will not alter the normal position of the magnetic needle, 5

thus showing the operator that the line tested carries alternating curren The face of the casing 1 is closed by a iianged cap 13 that rests against a transparent plate 14. The cap or face of the casing is provided with longitudinal and lateral openings 15 which extend from the center thereof, and through these openings, and through the plate 14 the position of the magnetic needle 4 is observable.

Having described the invention, I claim:

AnV electric polarity indicatorA comprising -a horseshoe magnet, a magnetized needle centrally pivoted between the polesv of the magnet and the ends of the horseshoe magnet terminatingV at opposite sides .of the pivot of the magnetized needle, an electro-magnet havingits core arranged at right angles tothe pivot of the needle and spaced therefrom and having its Winding at its outer end removably connected to a conduductor cord having a metal tip and a conductor'V 95 Wire connected to the Winding at the inner end of the electro-magnet, `and having removably secured thereto a conductor cord having a metal tip, and a casing for the electro-magnet and the horseshoe magnet, said casing having a substantially cross-shaped opening vin the top thereof through which the magnetized needle is visible.

FELIPE B. ACOSTA. 

